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jhollington · 3 Feb 2017, 10:29 AM

Yes, the updated SPF record looks syntactically correct, both based on what mavas posted and my own "dig" query (the different output is just two different tools — mavas used "nslookup" while I normally use "dig").

Switching the DNS around and testing with tonytonini.com could work as a test then if that's easier to do, however I'd suggest following the easier path first and simply changing the MX record on GoDaddy and leaving the DNS there, since moving DNS between providers can be more complicated and time-consuming.

Before you do this, however, see if GoDaddy will let you set the "TTL" to a lower value (according to this document, you should be able to). Right now the TTL for your MX records is set to 3600 seconds (1 hour), which means this is how long other servers will cache the last results. In other words, if you changed the MX record right now to 50Webs, it might take up to an hour before Comcast (or any other server) gets the message, and if tonytonini.com is a mission-critical domain, you don't want to risk interrupting mail flow for any longer than necessary, so waiting for an hour to get a successful test and then waiting another hour before you know for certain it's switched back wouldn't be a very good idea.

So what I'd suggest is the following:

Set the TTL of the MX record(s) for tonytonini.com to something very low. 60 seconds is a good number if at all possible.
Wait at least an hour to ensure that the old record has expired from any other name servers out on the Internet. If you're using Windows, you can check this from the command-line with the command [pre]nslookup -type=MX -debug tonytonini.com[/pre]. The nslookup command will also work on Mac, but I find dig produces easier-to-read results, so if you're on a Mac (or Linux), use dig mx tonytonini.com.
Once you're sure that you're getting the lower TTL value appearing, change the MX record on GoDaddy to point to 50Webs.
Wait a couple of minutes to make sure it's propagated. Again, the nslookup/dig commands above can be used to check this.
Try sending mail from Comcast.net webmail to your tonytonini.com address and see what happens.

If this is a DNS-related issue, then the test should be successful and the message should get through. If it's not DNS-related, then it will still fail and we've eliminated that as a possibility.

3 Feb 2017, 10:29 AM	#63
jhollington Essential Contributor Join Date: Apr 2008 Posts: 371	Yes, the updated SPF record looks syntactically correct, both based on what mavas posted and my own "dig" query (the different output is just two different tools — mavas used "nslookup" while I normally use "dig"). Switching the DNS around and testing with tonytonini.com could work as a test then if that's easier to do, however I'd suggest following the easier path first and simply changing the MX record on GoDaddy and leaving the DNS there, since moving DNS between providers can be more complicated and time-consuming. Before you do this, however, see if GoDaddy will let you set the "TTL" to a lower value (according to this document, you should be able to). Right now the TTL for your MX records is set to 3600 seconds (1 hour), which means this is how long other servers will cache the last results. In other words, if you changed the MX record right now to 50Webs, it might take up to an hour before Comcast (or any other server) gets the message, and if tonytonini.com is a mission-critical domain, you don't want to risk interrupting mail flow for any longer than necessary, so waiting for an hour to get a successful test and then waiting another hour before you know for certain it's switched back wouldn't be a very good idea. So what I'd suggest is the following: Set the TTL of the MX record(s) for tonytonini.com to something very low. 60 seconds is a good number if at all possible. Wait at least an hour to ensure that the old record has expired from any other name servers out on the Internet. If you're using Windows, you can check this from the command-line with the command [pre]nslookup -type=MX -debug tonytonini.com[/pre]. The nslookup command will also work on Mac, but I find dig produces easier-to-read results, so if you're on a Mac (or Linux), use dig mx tonytonini.com. Once you're sure that you're getting the lower TTL value appearing, change the MX record on GoDaddy to point to 50Webs. Wait a couple of minutes to make sure it's propagated. Again, the nslookup/dig commands above can be used to check this. Try sending mail from Comcast.net webmail to your tonytonini.com address and see what happens. If this is a DNS-related issue, then the test should be successful and the message should get through. If it's not DNS-related, then it will still fail and we've eliminated that as a possibility.